1096055 - pdf.js stops loading documents if too many (~20) pdf.js tabs are open

Status: RESOLVED FIXED

(Firefox :: PDF Viewer, defect, P3)

Description

[Zack Weinberg (:zwol)]

If you have many pdf.js tabs open at once (for instance, having opened lots and lots of papers in background tabs from a scholar.google.com search or five) you will eventually hit some sort of hard limit -- Ted M speculated it was dom.workers.maxPerDomain, being applied to all instances of pdf.js globally.  Tabs beyond this limit display the pdf.js toolbar but do not load or display the document.  (The dark gray background texture covers the entire content area, and the loading progress bar appears but remains at 0% forever.)  The toolbar in general behaves normally, e.g. you can show and hide the (empty) sidebar, and you can use the "download" button to extract the PDF into an external viewer.

I have not done an exact count but I think the limit is in the range of 20-25 open pdf.js tabs, which would be consistent with Ted's theory (the default value for dom.workers.maxPerDomain being 20).

Note that one might want many open pdf.js tabs from the same domain (consider dl.acm.org or arxiv.org) so ascribing whatever limited resource is involved to the content origin would be better but is not a complete fix.